Disposable hypodermic injection syringe



Nov. 2, 1954 w ug R ET AL 2,693,186

DISPOSABLE HYPODERMIC INJECTION SYRINGE Filed May 18, 1953 4Sheets-Sheet 3 INVENTORSS Mil/4M M Plum 5 1 24mm C. K/KER.

ATTORNEYS.

' the patient.

United States Patent DISPOSABLE HYPODERMIC INJECTION SYRINGE William M.Riker and Frankie C. Riker, Charlotte, N. C.

Application May 18, 1953, Serial No. 355,472

12 Claims. (Cl. 128 218) This invention generally relates to hypodermicsyringes and more especially to an improved automatic syringe sodesigned as to facilitate self-administration of the desired liquidmedicament by, the patient.

Hypodermic syringes currently in use require manual insertion of theneedle into the patient, which is often quite painful, and then manualactuation of a plunger causes injection of the dose through the needleand into This type of hypodermic syringe is useful only when operated bya skilled attendant.

It is the primary object of this invention to provide a compacthypodermic injection apparatus including a sealed pierceable ampule orcapsule and a tubular hypodermic needle, which are mounted in a sealedcasing, with manually releasable trigger operated means normallyretaining the needle in withdrawn position in the casing and wherein atrigger is provided which will automatically release the needle to causethe same to be automatically inserted under the skin of the patient andwherein means are provided which operate automatically immediatelypreceding insertion of the needle under the skin of the patient forpiercing the ampule and directing the medicament therefrom through theneedle and thus into the patient thereby enabling subcutaneous, orintra-muscular injections to be eifected single-handed by the patienthimself or by anyone skilled or unskilled in the use of hypodermicsyringes.

It is another object of this invention to provide an automaticdisposable hypodermic injection syringe of the character last describedwhich is sufficiently sturdy to enable its use for a one-shot operation,but which is compact and may be economically produced for sale at such arelatively low cost as to manifest its use in emergency first-aid kits,particularly of the type which may :3 carried in air-craft, trains,automobiles, boats and the It is another object of this invention toprovide a syringe of the type described wherein means are provided forautomatically insuring that the system is purged of air immediately uponthe device being activated and prior to the hypodermic needle beinginserted into the skin of the patient, thus automatically eliminatingthe danger of introducing air into the bloodstream of the patient.

Some of the obiects of the invention having been stated, other obiectswill appear as the description proceeds, when taken in connection withthe accompanying drawings. in which t Figure l is a side elevation ofthe improved hypodermic injection syringe showing the same with themovable parts thereof in inoperative position;

Figure 2 is an enlarged longitudinal sectional view taken substantiallyalong the line 22 in Figure 1;

Figure 3 is a fragmentary view similar to the central portion of Figure2, but showing the trigger and associated parts in position preparatoryto actuation of the trigger;

Figure 4 is a transverse sectional view looking up along the line 4-4 inFigure 3; Figure 5 is a longitudinal sectional view taken substantiallyalong the line 55 in Figure 2, but wherein the trigger has beendepressed and the capsule pierced to direct liquid to the needle;

Figure 6 is a transverse sectional view taken substantially along theline 6-6 in Figure 5;

Figure 7 is a transverse sectional view taken substantrally along theline 77 in Figure 5;

, 2,693,185 Patented Nov. 2, 1954 Figure 8 is a transverse sectionalview taken substantially along the line 8-8 in Figure 5;

- Figure 9 is a longitudinal section through the hypodermic syringesimilar to Figure 2, but being taken substantially along the line 99 inFigure 6; I

Figure 10 is a transverse sectional view taken substantially along theline 1010 in Figure 9;

Figure llis a fragmentary vertical sectional View, with parts brokenaway, taken substantially along the line 1111 in Figure 9;

Figure 12 is a view similar to Figure 9, but showing the capsulepuncturing means and the hypodermic needle in operative positions;

Figure 13 is an isometric view of portions of the trigger mechanism andbeing taken looking in the direction indicated by the arrow 13 in Figure3;

Figure 14 is an elevation of the sealing tab which normally closes thetrigger push button opening shown in Figure l, but looking at the inneror reverse side thereof;

Figure 15 is an enlarged view of the central portion of Figure 6 showingthe piercing needle;

Figure 16 is an enlarged sectional view through the hypodermic needletaken along line 1616 in Figure 12'.

Referring more specifically to the drawings, the numeral 1t broadlydesignates a cylindrical casing or housing of the disposable hypodermicsyringe, which is preferably made of plastic. The casing 10 is closed atits upper end by a plastic cap 11 which is shown as being fused to thecasing 10, but may be threaded thereon and which cap contains aresilient ampule or capsule 12 of an injection fluid or serum F. Thecapsule 12 may be 'adhesively secured in the concavity provided thereforin the cap 11 or may merely be frictionally retained therein. Thecapsule may be of the well known type having a soluble gelatinous wallcontaining approximately one cubic centimeter of fluid or any amountwhich will equal a normal injection according to medical practice.

The casing 10 is provided with an upper or first smooth bore or circularcavity 15, a slightly smaller medial or second bore or cavity 16 and aslightly smaller lower or third bore or cavity 17 therein whichcommunicate with each other and form shoulders 20 and 21 at their junctures. The lower end of casing 10 is closed by a closure member 22. Theupper bore 15 is provided with an upper or first circularly-shapedplatform or partition 25 which is suitably secured against the shoulder24 as by a plurality of plastic pins 26. The upper platform or partition25 is provided with a plurality of holes or openings 27 so that air maypass through the platform 25. The platform 25 is also provided with anupwardly extending tubular portion 30 surrounded by a coiled compressionspring 31 whose lower end bears against platform 25 and whose upper endbears against, and normally urges upwardly, an upper or first needleguiding sleeve or piston 32. The first piston is slidable in the bore 15of the cylindrical casing 10. The piston 32 is also provided withair-vent holes 33 and an inverted conical central portion 34 in whoserounded free end a tubular upper or capsule piercing needle 35 isfixedly mounted.

The conical portion 34 has a cavity 36 therein in which the coiled upperportion of a tube 44) is disposed. The lower end of the upper needle 35is connected to one end of the coiled tube 40. The lower end of the tube40 communicates with the upper end of a lower or hypodermic needle to belater described. The upper needle guiding sleeve or first piston 32 isnormally restrained against upward movement, otherwise effected by thecompression spring 31, by a pair of pins 41 and 42 (Figures 4, 5, 7, l0,l2 and 13), whose upper ends are fixed to the piston 32 and which extenddownwardly through respective slots 43 and 44 in the first or upperplatform 25. The pins 41 and 42 are provided with eyes 45 at their lowerends which are normally engaged by legs 48 and 49 of a substantiallyW-shaped actuating arm or latch member 50 (Figures 3, 4, 5, 7, 9, 10 and13). It is thus seen that, when the legs 48 and 49 of the actuating arm50 are in the eyes 45 of the pins 41 and 42, the first piston 32 isrestrained from upward movement.

The medial portion of the actuating arm 5th passes through a lateralsubstantially L-shaped slot 52 in an actuating trigger broadlydesignated at 55. The actuating trigger is slidably mounted in a pair ofguide blocks 56 and 57 which, as best shown in Figures 2, 3, 4, 5, 10and 13, are integral with a lower or second platform or partition 60.The lower platform is circular and fits in the bore 16 of the casing 10and is suitably secured against the shoulder 21, as by a plurality ofplastic pins 58 which extend through the Wall of casing 10. The lowerplatform 60 is also provided with air passage holes 59 therein.

The actuating trigger 55 is normally urged outwardly, away from thecenter of the casing 10, against a pliable sealing element 61 (Figures1, 2 and 14) which preferably has a circular adhesivesurface 62 thereonand a pull tab 63 integral therewith. The sealing element 61 is adaptedto be placed over and seal an opening 65 in the casing 10. The actuatingtrigger 55 has a reduced portion 66 thereon which is adapted to moveoutwardly to cocked position, through the opening 65, upon removal ofelement 61. The reduced portion 66 of the actuating trigger 55 may alsobe termed a push button and is normally urged through the opening 65 inthe casing 10 by an endless resilient or elastic band 70 (Figures 2, 3,4, 9, 10, 12 and 13) which passes across the inner end of the trigger55, over the medial portion of the actuating arm 50 at each side of theactuating trigger 55 and upwardly through a pair of slots 71 and 72 inthe upper or first platform 25 (see Figures 2, 3 and 7). It is thus seenthat, upon removing the sealing element 61 from the casing 10, theactuating trigger 55 is moved from the position shown in Figure 2 to theposition shown in Figure 3 by the resilient band 70 which also causesthe medial portion of the actuating arm or latch member 50 to moveupwardly into the vertical or axial leg of the L- shaped slot 52 to thuscock the trigger mechanism.

The lower or second platform or partition 60 is also provided with adownwardly projecting tubular portion 76 surrounded by a coiledcompression spring 77. The upper end of spring 77 bears against theplatform 60 and the lower end thereof bears against a lower or secondpiston or needle guiding sleeve 80 mounted for longitudinal or axialsliding movement in the lower or third bore 17. The lower piston 80 isprovided with an intermediate web portion 81 having air-vent holes 82therein in which a tubular lower or hypodermic needle 83 is fixedlymounted. The outer or lower end of .needle 83 is sliclably mounted in anopening 85 in thelower .end 22 of the casing 10.

The inner end of the hypodermic needle 83 has the lower end of thecoiled tube 40 communicatively connected thereto. The tube 40 has astraight central portion which loosely extends through an opening 89formed in the lower platform 60, through an elongated slot 90 formed inthe trigger 55, and upwardly through an opening 91 formed in the upperplatform .25.. piston 80 is normally restrained .from downward-movement,otherwise effected by thecompressionspring 77, .by a pin 92 (Figures 9.,ill and 12) whose lower end isfixed in the web 81 of the lower piston 80and whose upper end passes through a slot 93 .formed in .the lower orsecond platform 60.

The pin 92 extends upwardly beyond platform 60 and has an eye 94 thereinwhich is loosely penetrated bya curved leg 95 of a second latch memberbroadly designated at 96 (Figures 9, 1'0 and 12). The latch 96 ispreferably made from a light material, such as a small wire, and has acurved leg .97 which passes throughthe lower open end of a latchactuating member 100. The member 100 passes upwardly through a slot 101formed in the upper platform 25 and is formed with a loop 104 whose sideportions loosely pass through a pair of passageways 102 in the upperneedle guiding sleeve or first piston 32. It is thus seen that the leg95 of latch 96 normally prevents the eye 94 of the pin 92 from passingdownwardly through the slot '93 in the lower platform 60 to thus preventthe lower needle 83 from'being moved downwardly by the compressionspring 77, until the pin 92 is released from the latch 96.

The lower end of the casing '10 is provided with an annular groove 105in which a thin walled inner cap 106 is mounted. The cap 106 is madefrom a material which is easily penetrated by the needle 83, such asplastic, aluminum foil or the like. The cap 106 is circular and coversthe lower end of the casing '10 of the hypodermic syringe to seal thelower end of the hypodermic "syringe.

The lower The inner cap 106 is provided with a circularly-shaped sponge107 fixed to its outer surface, as by an adhesive, and which may besaturated with alcohol or any other antiseptic solution. An outer cap108, also preferably made from the same material as the inner cap 106,is placed around the sponge rubber disc 107 and is preferablyheat-sealed to the inner cap 106 at its outer edges.

A.cord,.rip wire or tear-strip is sealed between the caps 106 and1'08-and the free end thereof extends through the outer cap 108 and maybe pulled by the patient to rip away the outer cap 108, asshownin Figure5. The side walls of the inner cap 106 and the outer cap 108 are sealedtogether in the annular groove 1105 around the lower end of the casing10 of the hypodermic syringe and held in this groove by an adhesive band111 preferably made from a viscose material.

Method of operation Since this hypodermic syringe is adapted to be usedforemergency use and carried in an emergency first-aid opening 65 in thecasing 10 to the position shown in Figure '3. This action causes thevertical or axial leg of the L-shaped slot 52 to become alined with themedial portion of the first latch or actuating arm 50, which then movesupwardly into the vertical leg of the slot 52 to cock the triggermechanism. Thus, upon inward movement of the push button 66 by anoperator, the actuating arm 50, along with the legs 48 and 49, is movedto the left of the position shown in Figure 4 or to the position shownin broken lines in Figure 7.

As soon :as the tab 61 has been removed and the plunger movedoutwardlyby the resilient band 70 in the manner just described, the pullcord or wire 110 at the lower end of the casing "10 of the hypodermicsyringe should be pulled around the outer periphery thereof to tear theouter'cap 108 apart from the lower end of the hypodermic syringe so thesponge 107 is exposed and may be rubbed on the area to be punctured bythe hypodermic needle 83 to sterilize and cleanse the area of the skininto which the hypodermic needle is to be inserted. The circularlyshapedsponge 107 is then centered upon the portion of the patients skin intowhich theneedle is to be inserted and the actuating-triggerSS, which isthen in the position shown in Figure '3, is moved inwardly by theoperator to cause the actuating lever 50 and the legs 48 and 49 to movefrom the position shown in Figure 4 to the broken line position shown inFigure 7. This moves the legs 48 and 49 out of the eyes 45 in therespective pins 41 and 42 to release the upper needle guiding sleeve orfirst piston 32,'which then darts upwardly or outwardly to substantiallythe position shown in Figure 5 by virtue of the compression spring '31.In so doing, the upper needle 35 pierces the capsule 12 and the pressureof the spring 31 forces the injection fluid F, under pressure, into thehollow capsule puncturing needle 35, through the coiled tube 40, intoand through the hypodermic needle 83 to thereby exhaust any air from thehypodermic needle 83. As the pins 41 and 42 are released by theactuating arm 50, the spring 31. initially imparts rapid movement to theneedle 35 from substantially the position shown in Figure 5, thusquickly piercing the capsule 12. However, as the capsule 12 is pierced,the lower end of the capsule 1'2 is engaged by the inverted conicalportion 34 of the upperneedle guiding sleeve or first piston 32 and,since there is some resistance to the flow of fiuid through the smallcoiled tube 40, the compression spring 31 slowly moves the upper needle35 into the capsule 12, thus collapsing the capsule 12 and forcing thefluid F slowly through the upper needle 35, the coiled tube 40, thelower or hypodermic needle 83 and into the patient. it might be statedthat the desired rate of flow of the injection fluid F may be controlledby varying the size of the compression spring 31.

When the upper needle 35 .has reached the position shown in Figure 5 theinjection fluid F will have entered the tube 40 and the lower needle.83, and by this time, Only a drop of injection fluid is forced from thelower I moves the upper release pin 100 from the position shown inFigure 9 to substantially the position shown in Figure 12. In so doing,the latch member96 swings away from partition 60 while rotating enoughso that the leg 95 is withdrawn from the eye 94 at the top or free endof the pin 92 (Figures 9, 10, 11 and 12) to thus release the pin 92.This permits the compression spring 77 to move the lower needle guidingsleeve or second piston 80 downwardly or outwardly very rapidly topierce the skin of the patient. This relatively fast insertion of thehypodermic needle into the skin of the patient renders the injectionitself relatively painless.

It is thus seen that, as the hypodermic needle 83 is inserted into theskin of the patient, the upper or first compression spring 31 continuesto force the upper or first needle guiding sleeve or piston 32 upwardlyto collapse the capsule 12 and force the injection fluid F through theupper needle 35, the coiled tube 40, the lower needle 83 and into thepatient. After the capsule 12 has been collapsed and the fluid F forcedinto the patient, the needle 83 may then be extracted and the disposablesyringe may then be discarded.

It is thus seen, that we have provided a disposable hypodermic syringewhich is so compact, so easily operated and may be so economicallyproduced as to manifest its use in emergency first-aid kits and whichhas a sealed container in which a single shot of liquid medicament isprovided 'so that, when the injection is administered, the possibilityof air being introduced into the patients bloodstream, or of the patientreceiving an overdose of medicament is obviated. Thus, the medicamentmay be procured from druggists by authority of a doctors prescription.improved syringe may be used for self administration of insulin'fordiabetic patients, for self administration of an anaesthetic, as may berequired by military personnel in combat or by sportsmen and for manyother purposes.

The improved syringe may be sterilized while it is being assembled andthe operating parts thereof will be maintained sterile until the fluid Fis discharged through the hypodermic needle 83. The possibility of itsre-use 1. A hypodermic injection syringe comprising acasing, an upperneedle and a lower needle slidably mounted in said casing, a resilientcapsule normally spaced from said upper needle, communicative meansbetween said upper needle and said lower needle, resilient meansnormally urging said upper needle upwardly toward said capsule, manuallyreleasable restraining means for restraining said upper needle againstupward movement, resilient means urging said lower needle downwardly,releasable restraining means for restraining said lower needle againstdownward movement, and means operable automatically in the course ofupward movement of said upper needle for releasing said lower needlefrom the latter restraining means.

2. A hypodermic injection syringe comprising an elongated casing, afirst needle and a second needle mounted for longitudinal movement insaid casing, communicative means between said first and second needles,a resilient capsule fixed in said casing adjacent said first needle andcontaining an injection fluid, resilient means normally urging saidfirst needle toward said capsule, manually releasable restraining meansfor restraining said first needle from engaging said capsule, resilientmeans normally urging said first needle outwardly relative to saidcasing, releasable restrainingmeans for restraining said second needleagainst outward movement,

Particularly in the case of transients, theand means operableautomatically in the course of movement of said first needle intopiercing engagement with said capsule for releasing said second needlefrom th latter restraining means.

3. In a hypodermic syringe having an elongated casing adapted to supporta resilient pierceable ampule of injection fluid adjacent one endthereof; the combination of a tubular hypodermic needle and a tubularpiercing needle mounted for relative substantally axial movement in saidcasing, spring means normally urging the two needles away from eachother, manually releasable means normally maintaining the piercingneedle in inward position spaced from the ampule, restraining meansconnecting the piercing needle with the hypodermic needle and being soarranged as to maintain the hypodermic needle in inward position whenthe piercing needle is in inward position, an extensible tubular elementcommunicatively connecting the piercing needle with the hypodermicneedle whereby the piercing needle will be released and moved outwardlyby said spring means upon being released from said releasable means, andmeans operable automatically upon outward movement of the piercingneedle a predetermined distance for releasing the hypodermic needle fromthe restraining means whereby the hypodermic needle is subsequentlyurged outwardly by said spring means.

4. A hypodermic syringe comprising a casing, a resilient pierceablecapsule containing an injection fluid therein carried by said casing,first and second tubular needles mounted for relative movement in saidcasing, a tube communicatively connected to corresponding ends of saidneedles, resilient means for urging the first tubular needle toward thecapsule and for urging the second needle outwardly relative to saidcasing, means for maintaining the first and second needles in withdrawnposition relative to the capsule and the casing respectively, manuallyoperable means for releasing the means for maintaining the first andsecond needles in withdrawn position, and said means for maintaining thefirst and second needles in withdrawn position being so arranged as topermit the first and second needles to move outwardly in succession uponoperation of said manually operable means whereby the first needlepenetrates the capsule to direct fluid therefrom into and through thesecond needle preceding outward movement of the second needle relativeto said casing.

5. A hypodermic syringe comprising a casing, a resilent pierceablecapsule for containing an injection fluid therein, first and secondtubular needles mounted for relative movement in said casing, anextensible tube communicatively connected to corresponding ends of saidneedles, said casing having means for supporting said capsule adjacentsaid first tubular needle, first resilient means for urging the firstneedle toward the capsule, second resilient means for urging the secondneedle outwardly relative to said casing, means for maintaining thefirst and second needles in withdrawn position relative to the capsuleand the casing respectively, manually operable means for releasing themeans for maintaining the first and second needles in withdrawnposition, and'said means for maintaining the first and second needles in.withdrawn position being so arranged as to permit s'uccessive outwardmovement of the first and second needles upon operation of said manuallyoperable means under the impetus of said resilient means whereby thefirst needle penetrates the capsule to direct fluid therefrom into andthrough the second needle preceding outward movement of the secondneedle relative to said casing.

6. A hypodermic syringe comprising an elongated casing, a pierceableresilient ampule of injection fluid fixed adjacent one end of saidcasing, a tubular hypodermic needle and a substantially axially alinedtubular piercing needle mounted for relative axial movement in saidcasing, spring means normally urging the two needles away from eachother, a trigger mechanism, means engaged by the trigger mechanism fornormally maintaining the piercing needle in inward position spaced fromthe ampule, a latch means connecting the piercing needle with thehypodermic needle and being so'arranged as to maintain the hypodermicneedle in inward position when the piercing needle is in inwardposition, an extensible tube communicatively connecting the'proximalends of the piercing needle and the hypodermic needle, said triggermechanism being operable to release the piercing needle from said meansengageable thereby upon manipulation :thereof whereby the piercingneedle will be'movedvoutwardly by said spring means to pierce saidampule andtdirect fluid to said hypodermic needle, and means operableautomatically upon said piercing needletentering said ampule forreleasing the hypo'dermic :need'le from the latch means whereby thehypodermic needle is urged outwardly by said sprlng means.

"first and second substantially axially a'lined needle guiding elements:mounted for axial movement in said casing adjacent the respective firstand second ends of said casing, a tubular capsule piercing needlecarried by the first needle guiding element, a tubular hypodermic needlecarried by the second needle guiding element, manually releasable meansnormally maintaining the capsule piercing needle in spaced relation fromsaid capsule, latch means normally restraining the hypodermic needlefrom moving outwardly through said second end of said casing, .anextensible tubular connection between the capsule piercing needle andthe hypodermic needle, resilient means automatically operable uponreleasing said releasable means for moving the piercing needle into thecapsule for directing the fluid from the capsule into said hypodermicneedle, means responsive to the movement of the capsule piercing needleinto the capsule for releasing the hypodermic needle from said latchmeans, and resilient means for urging the hypodermic needle outwardlythrough said second end of the casing upon said latch means beingreleased.

8. A hypodermic syringe comprising a casing having means for supportinga pierceable resilient capsule of injection fluid therein adjacent oneend thereof, first and second needle guiding elements mounted forrelative movement in said casing adjacent opposite ends of said casing,a tubular capsule piercing needle carried by the first needle guidingelement and extending toward said capsule, a tubular hypodermic needlecarried by the second needle guiding element, manually releasable meansnormally maintaining the capsule piercing needle in spaced relationfrom'said capsule, latch means normally restraining the hypodermicneedle from moving outwardly through said casing, a tubular connectionbetween the capsule piercing needle and the hypodermic needle, resilientmeans automatically operable upon releasing said releasable means formoving the piercing needle into piercing engagement with the capsule fordirecting the fluid from the capsule into said hypodermic needle, saidfirst guiding element having a portion thereon adjacent the piercingneedle for exerting pressure on said capsule to thereby force the fluidinto the needles, means responsive to the movement of the capsulepiercing needle into the capsule for releasing the hypodermic needlefrom said latch means, and resilient means for urging the hypodermicneedle outwardly relative .to said casing upon said latch means beingreleased.

9. A hypodermic syringe comprising a cylindrical casing provided with apartition intermediate the ends thereof, a first piston mounted foraxial movement insaid casing adjacent one side of said partition, asecond piston mounted for axial movement in said casing adjacent "theother side of said partition, a pierceable resilient capsu'le forcontaining injection fluid, means supporting said capsule in thecylinder and being spaced from the side of the first piston remote fromsaid partition, a first tubular needle carried by said first piston :andextending outwardly therefrom toward said capsule, a second tubularhypodermic needle carried by the second piston and extendingoutwardlytherefrom away'from said partit'ion, first and second latch meansnormally maintaining the respective first and second pistons in inwardposition whereby the first needle is spaced from said capsule and :thehypodermic needle is enclosed within said casing, a pliable tubeconnected at its distal ends to the proximal ends of said first andsecond needles, manually operable means for releasing the first pistonfrom the first latch means, resilient means for urging the first pistonaway from the partition upon operation of said manually operable meanswhereby the first needle will penetrate said capsule and the pressure ofsaidfirst piston against the capsule Wlll cause the fluid .to flow fromthe capsule into said hypodermic needle under 8 pressure, means operable:automaticaldyiuponithe piston engaging "said capsule for releasing thesecond piston from the second latch means, and resilient means forurging .the second :piston .and its needle away from the partition uponthe :second piston being released from the second latch means. 1

.10. A hypodermic syringe comprisinga sealed cylindrical casing providedwithsa partition intermediate the ends thereof, a first piston mountedfor axial movement saidzcasing adjacent ones'ide of said partition, 21second xpiston mounted for axial movement in said casing adjacent theother :side of said partition, means for supporting a resilient capsulecontaining injection fluid in the cylinder adjacent the side of thefirst piston :re- .mote from said partition, a 'first Ltubular needlecarried by said first piston and extending outwardly therefrom towardsaid capsule, 'a second tubular hypodermic needle carried by the secondpiston and extending outwardly therefrom away from :said partition,tneans penetrable by said second needle "for closing the end of saidcasing adjacent the outer end of the second needle, first and secondlatch :means nomiallyrmaintaining the respective first and second:pistons in inward position whereby the first :needle is spaced fromsaid capsule and the second needle is enclosed -within said casing, acoiled plia'ble tu'beconnected at :its .distal :ends to the proximalends of said first and second needles, manually operable means .forreleasing the first piston from the first latch means, resilient meansfor urging the first piston away from the partition upon operation ofsaid manually operable means whereby the first needle Willpenetrate saidcapsule and the pressure of said first piston against the capsule-willcause 'the'fluid to flowfrom the capsule into said second needle underpressure, means operable automatically upon the *first'piston 'engagingsaid capsule for releasing the second piston from the second latchmeans, and resilient means for urging thesecond piston and its needleaway from the partition upon the :second piston being released from thesecond latch means whereby the second needle will :dart outwardlythrough :said penetrable means.

11. A hypodermic syringe comprising a casing havmg a cylindrical walland a cover closing a first end thereof and a closure member closing asecond end thereof opposite from the tint :end, a pierceable resilientcapsule adapted to contain a supply of injection fluid carried by saidcover and projecting inwardly there from, a first tubular capsulepiercing needle mounted for longitudinal movement in said casingadjacent said capsule, a second hypodermic needle mounted for axialmovement in said closure member, first :and second resilient means forrespectively urging said first and second needles apart from each other,an actuating arm, a releasable connection between said actuating arm andthe first needle whereby said actuating arm normally maintains the firstneedle in'spaced relationship from the capsule, a trigger mechanismmovably mounted in said casing and having a portion radially movablethrough the wall of said casing, manually operable means "normallymaintaining the trigger mechanism in uncocked position, means responsiveto movement of said manually operable means for moving the triggermechanism to cocked position, said portion of the trigger mechanismbeing movable outwardly relative to said casing when the triggermechanism is moved to cocked position, means operable automatically uponsubsequent inward movement of said portion of the trigger mechanism forreleasing said connection from the actuating arm whereby the firstresilient means causes the first needle to pierce the capsule, a tubularconnection between the first and second needles for directing the fluidfrom the capsule, through the first needle and thence through the secondneedle, latch means for maintaining the second needle in withdrawnposition relative to said closure member, and means operableautomatically upon said first needle piercing said capsule for releasingthe second needle from the latch means whereby the second for urgingsaid trigger mechanism outwardly upon said pliable element being tornaway from said portion, said trigger mechanism having an irregularopening therethrough through which a portion of said actuating armloosely extends, said irregular opening defining a shoulder which isoff-set relative to the portion of said arm extending therethrough whensaid trigger mechanism is uncocked, and the latter resilient means alsoserving to urge said portion of said arm into the path of said shoulderwhen the trigger mechanism is cocked whereby subsequent depression ofsaid portion of the trigger mechanism will move the actuating arm out ofengage- 10 ment with said connection extending to the first needle torelease the same.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,413,303 Folkman Dec. 31, 1946 FOREIGN PATENTS Number CountryDate 378,714 Germany July 30, 1923

